this bug has been around since a bit before 1.4.  see

http://www.NetBSD.org/cgi-bin/query-pr-single.pl?number=5714
http://www.NetBSD.org/cgi-bin/query-pr-single.pl?number=7559
http://www.NetBSD.org/cgi-bin/query-pr-single.pl?number=7442
http://www.NetBSD.org/cgi-bin/query-pr-single.pl?number=5641
http://www.NetBSD.org/cgi-bin/query-pr-single.pl?number=6742

-Chuck


On Fri, Dec 17, 1999 at 03:37:54AM -0800, Todd Whitesel wrote:
> Sparc IPX, 32 megs memory. Sources checked out -D "19991209 UTC".
> 
> Happened once when I first booted the new kernel, then a few hours into the
> make build (soon after dependall ===> libc it turns out), it hit again. This
> is what I got the second time.
> 
> (gdb) target kcore netbsd.0.core
> panic: illegal instruction
> #0  0xf006e510 in mi_switch ()
> (gdb) bt
> #0  0xf006e510 in mi_switch ()
> #1  0xf006dce8 in tsleep ()
> #2  0xf0178528 in uvm_scheduler ()
> #3  0xf005d724 in check_console ()
> #4  0xf000986c in cpu_hatch ()
> can not access 0x30784c, invalid address (30784c)
> can not access 0x30784c, invalid address (30784c)
> can not access 0x30784c, invalid address (30784c)
> can not access 0x30784c, invalid address (30784c)
> can not access 0xefffffd8, invalid address (efffffd8)
> can not access 0xefffffd8, invalid address (efffffd8)
> Cannot access memory at address 0xefffffd8.
> (gdb) disas 0xf006e500 0xf006e520
> Dump of assembler code from 0xf006e500 to 0xf006e520:
> 0xf006e500 <mi_switch+404>:     or  %o2, 0x370, %o2     ! 0xf027bf70 <uvmexp>
> 0xf006e504 <mi_switch+408>:     ld  [ %o2 + 0x6c ], %o1
> 0xf006e508 <mi_switch+412>:     mov  %l2, %o0
> 0xf006e50c <mi_switch+416>:     inc  %o1
> 0xf006e510 <mi_switch+420>:     call  0xf0009ea8 <cpu_switch>
> 0xf006e514 <mi_switch+424>:     st  %o1, [ %o2 + 0x6c ]
> 0xf006e518 <mi_switch+428>:     call  0xf0192460 <microtime>
> 0xf006e51c <mi_switch+432>:     or  %l3, 0x10c, %o0
> End of assembler dump.
> (gdb) 
> 
> I don't have a lot of experience with these on sparc yet -- is this likely
> to be a kernel bug, or the cold weather irritating this ancient IPX I bought
> on the cheap a few months ago?
> 
> Todd Whitesel
> toddpw @ best.com